Question

A permanent magnet in the shape of a thin cylinder of length 10 cm has magnetisation (M) = 106 A m-1. It’s magnetization current IM is

• A. 105A
• B. 106A
• C. 107A
• D. 108A

Answer 1

Answer: (A)

105A

Answer 2

: As $\mathrm { Bl } = \mu _ { 0 } \mathrm { MI } = \mu _ { 0 } \left( \mathrm { I } + \mathrm { I } _ { \mathrm { M } } \right)$

Here, $\mathrm { I } = 0$

Then ,

$\Rightarrow \mathrm { I } _ { \mathrm { M } } = \mathrm { MI } = 10 ^ { 6 } \times 0.1 = 10 ^ { 5 } \mathrm {~A}$